水平井连续油管钻磨桥塞工艺研究与应用

针对连续油管钻磨桥塞过程中经常由于工艺参数选择不合理导致施工效率低的问题,通过分析连续油管钻磨工艺特点、钻磨工具的工作特性以及井底磨屑在不同井段的运移规律,结合"上提扫屑和定点循环"的钻除桥塞模式,对施工工艺进行了调整,对工作参数进行了优化,形成了水平井连续油管钻磨桥塞的工艺方案:选用PDC镶齿5刀翼磨鞋,螺杆钻具选择"中扭矩、中转速"工作模式,排量不低于420 L/min,钻压控制在14.7~19.6 kN。该工艺在数十口井进行了现场应用,与优化调整前相比,单个桥塞的平均钻除时间缩短46.5 min,钻磨动力液消耗量减少49.4%,一趟钻具能够连续钻除12个复合桥塞。应用结果表明,连续油管钻磨桥塞工艺在压裂后可以迅速恢复井筒畅通,达到提速增效的目的,具有很好的推广应用价值。 

Research and Application of Drilling,Milling-Grinding Techniques for Drilling out Composite Bridge Plugs in Coiled Tubing in Horizontal Wells

Due to the selection of improper parameters, the operational efficiency is low in the application of tubing drilling and grinding technology to drill and mill the bridge plug. Through the analysis of the characteristics of coiled tubing drilling and milling/grinding process, the working performance of drilling tools and the carrying regularity of cuttings at different sections of wellbore hole drilling, combined with the mode of drilling bridge plug:"cleaning cuttings by pulling up making circulationling at a fixed point", the operations were improved, technology was optimized, the working parameters were optimized, and a technical scheme of drilling and milling the bridge plug in the working mode of the horizontal wells was implemented. The PDC mill shoe bit with 5 blades and PDM screw drilling tools featured as medium torques and rotation speeds have been selected. It is recommended that the flow rate displacement should be maintained no lower than 420 L/min, and the weight on bit should be controlled within 14.7-19.6 kN. These technology processes have been carried out in several wells in the field. The average drilling time of a single bridge plug is shortened by 46.5 min compared with the performances before optimization and adjustment, and the consumption of drilling fluid is reduced by 49.4%. Twelve composite bridge plugs can be removed by running drilling strings once. The application results showed that the techniques of coiled tubing drilling and milling and grinding can quickly restore wellbore flow after fracturing and increase drilling efficiency. Consequently, it is worth promoting and applying widely.